Sources said surveillance footage shows the suspect casually walking away from the scene of the shocking crime on 122nd Street, near Claremont Avenue, Wednesday evening after a point-blank shooting of Amaury Rodriguez, 30, Heriberto Suazo, 26 and Luis Catalan, 25, who has a year-old son.

"These guys are marijuana dealers who have engaged in ripping off other dealers," a police source said of the victims.

The gunman was sitting in driver's side rear seat of the $88,000 car, which was parked near the Manhattan School of Music and the Theological Seminary, with the three victims when he took out a revolver and began blasting, sources said.

Amaury Rodriguez, 30, was one of three men killed near Columbia University on June 7, 2012.View Full Caption

NYS Department of Correction

The gunman shot Catalan, of the Upper East Side, who was sitting next to him in the back seat, in the left temple and left arm, according to the sources.

Then he turned the gun on the other two men, blasting Suazo, who was sitting in the front passenger's seat, in the back of the head and then hitting Rodriguez, who was sitting in the driver' seat, in the upper chest, upper right shoulder and right side of the neck before fleeing down 122nd Street towards Broadway.

All three men have men have extensive criminal records that include selling or possessing pot and have been suspected of robbing drug dealers, sources said.

Among the 25 arrests that Rodriguez, who served state time for weapons possession, has racked up are selling marijuana, felony assault and gun possession, sources said. Suazo had three arrests for felony assault, robbery and weapons possession as well as for allegedly having marijuana in Yonkers, sources said.

Sources said that a bystander walked past and saw Suazo leaning against the front passenger's side window wearing a Yankees hat and appearing as if he were sleeping.

He thought Rodriguez was sleeping as well, but noticed that his shirt was drenched in blood.

The alarmed witness alerted other bystanders, who then flagged down a passing patrol car from the 28th Precinct who radioed for backup.

Another witness, a 65-year-old maintenance worker whose name is being withheld by DNAinfo.com New York, said that he noticed three men "talking" in the BMW 750Li as he walked his wife to the bus stop around 5:30 p.m.

But when he returned to the scene a half hour later, he was shocked to find a swarm of police around the luxury car, which reportedly had license plates that didn't match its registration.

"I...saw the three men lying there," said the witness. "They were big men lying inside the car."

The man in the rear passenger seat "had his arms outstretched embracing the front seat," the witness said.

"I didn’t want to take a look anymore," he added.

Police believe the car "had not been parked there for an extended amount of time, perhaps an hour or so," before it was found, according to chief NYPD spokesman Paul Browne.

No drugs or a gun, or shell casings were recovered at the scene, which is why cops believe a revolver was used.

There also did not appear to be any signs of a struggle in the vehicle, which was owned by Rodriguez, sources said.

Adding to the mystery of the killings was that there were no reports of shots fired and no 911 calls, despite the fact that a class at Knox Hall of Columbia University's Union Theological Seminary were inside the building during the time of the shooting.

A text message from the school's administrators said that "there is no apparent involvement by members of the Columbia community." A university spokesman declined further comment.

At the 26th Precinct Catalan's grieving mother, Norma, remembered her son as a "hard worker."

"He was a good son," she said. "He was a good son."

She said that Catalan, who had a year-old son, Noah, with his live-in girlfriend, worked in the music industry.

"He used to call me 30 times a day, just to ask, 'How are you? How's the business?" the mom said. "You never hear about a son telling his mother 24/7, 'I love you.' 'I love you.'"

Catalan's family members said that they didn't recognize the name of Rodriguez and Suazo, both of Washington Heights.

His uncle, Joe Castellar, 54, said that Catalan was a "hard-working kid" who worked with his mother at a dog grooming center and volunteered at a local youth center.

''Even though he was allergic, he'd work around it," Castellar said. "He was a very likable young man, very charismatic. He was very visionary. He had a lot of ideas.''

He also said that his nephew was a dedicated dad who was devoted to his son and his family.

''Noah meant the world to him, and when he became a father, he was so proud," he said.

"He was always talking about his family. A lot of people loved Luis. The media wants to make this a drug deal gone bad, but I never knew him to do that.''

At Suazo's home in Washington Heights, relatives gathered to console each other.

"I got a big pain of losing my son," said Suazo's father. "I want to know who did it."

Rodriguez's mom was too distraught to talk, but a friend, who only gave his name as Biggie, called the victim a "role model."

"He grew up here, he's like a brother to me," Biggie said. "He's a role model to me."

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